Cooling a 2.0 16v - rad fan (new switch fitted..)

[Toad 0]

Is my meat not good enough for him now?

 

Shame really, as we'd have had a good chance of sorting it between us!

[Jim 2]

I'd have loved to have come down for a social mate - would have been a good laugh, but its mine and my missus's anniversary of going out so i'm spoken for, for the evening! If you're doing another BBQ or get together or something in the coming months, i'd love to come visit.. but its also a heck of a drive - you're 100 miles away!

 

Schteve - i'm not sure if my wiring is suspect or not mate! I hope it isn't?! :) Not checked the wiring yet - maybe tomorrow evening if it stops raining long enough..? :)

[Jim 2]

Can't find the correct P/N for the sensor. On the invoice when I got it, I remember now that they ordered me the wrong one - so I returned it and they sent off for what they thought was the right one, but I didn't get a new invoice when it came so have the wrong P/N on the sheet :(

[radness 0]

The Rad fan kicks in at 110 too so think this is right as well

 

That means the thermoswitch is only working at the second stage (ie it's 'failed safe') - cheap and easy part to change (30mm spanner needed)

 

1 = 84-91c

2 = 95-102 c

 

Can you show me picture of what you're changing here and what the part number is please? I'm a bit of a newbie :)

 

I have the exact same issue, drive the nuts off my car and it stays below 90C (water) and 100c (Oil) but drive slow and sit in traffic and water goes above 100c and oil 118c (it seems to be getting a bit higher), I opened the hood when it was this hot and the fan was going, but didn't appear terribly fast, and it stopped after opening the hood. I do think the temps are right as the bonnet does feel pretty hot to me and people have commented on the heat from the engine bay.

 

I checked my coolant and it's pretty dark and dirty, is this old age? It states that it uses G11, should i upgrade this to the new coolant? Is there much advantage as i did read a bit of the process and it seems a bit risky with getting air in the system etc... :(

 

Also, one last thing, my coolant level is half way between the top of the container and the "max" fill line,(appears to be over filled) is this bad? whats the best way of draining it?

[davidwort 0]

...I have the exact same issue, drive the nuts off my car and it stays below 90C (water) and 100c (Oil) but drive slow and sit in traffic and water goes above 100c and oil 118c (it seems to be getting a bit higher), I opened the hood when it was this hot and the fan was going, but didn't appear terribly fast, and it stopped after opening the hood. I do think the temps are right as the bonnet does feel pretty hot to me and people have commented on the heat from the engine bay.

 

I checked my coolant and it's pretty dark and dirty, is this old age? It states that it uses G11, should i upgrade this to the new coolant? Is there much advantage as i did read a bit of the process and it seems a bit risky with getting air in the system etc... :(

 

Also, one last thing, my coolant level is half way between the top of the container and the "max" fill line,(appears to be over filled) is this bad? whats the best way of draining it?

 

check the level with the engine cold, it can rise when hot (it is an expansion tank after all :) )

if it's too full when cold take the cap off an siphon a bit out with a short length of hose

I've tried G12+ in several cars instead of G11/generic blue coolant and it makes zilch difference to temps unless you massively over concentrate with either, the main advantage is G12+ has more stable corrosion inhibitors and is less harmfull to the environment.

 

with the fan speeds, you can always bridge the terminals to see what the two speeds sound like, 1 is a gentle hum/spin, 2 is much louder and faster, at idle speed warmed up from cold it should just click onto speed 1, 2 should only be reached if you've been on a long hard run and suddendly slow down/stop and lots of heat in the block needs dissipating

 

Pattern radiators don't help as they are less efficient at cooling so the fans have to work harder.

[radness 0]

Guys I look at my engine bay a bit confused...while trying to do what you suggest :(

 

where do i "short" the wires on the fan to test to make sure it isn't my rad switch thats not allowing the 2nd (slow speed) fan to come on? it's really starting to annoy me, i don't have a haynes manual yet and i'd like to get this sorted, if someone could take a picture or two of what i should try "shorting" out, i don't want to be an idiot and short the wrong thing, i assume i pull off the 3 wire plug that connects to the rear of the fan and do something here? but what? im a bit clueless :cuckoo: and only end up with hands covered in muck after half an hour poking around my engine bay deciding on what to tinker with :gag: lol

 

Just to be clear, it's a 9a, i have that relay thing beside my coolant, my fan comes on at 100c coolant and 110/118 oil :(

 

It's worse when im sitting in the drive though with no air flow, feels like i could be cooking the burgers on my engine block, as soon as im moving i have no issues, all stays at 90c coolant 100c oil, thats normal right?

 

Please help :clap:

[radness 0]

Anyone? :sad:

[davidwort 0]

your normal running oil and water temp is fine

 

if the 2L is the same as the 1.8 then there are 3 wires to the radiator temp sensor, live feed and switched feed out to fan speed 1 and fan speed 2, so unplugging the connector and bridge from live to the other pins will run your fan on speed 1 or 2 depending on which of the pins you bridge the live to.

[radness 0]

your normal running oil and water temp is fine

 

if the 2L is the same as the 1.8 then there are 3 wires to the radiator temp sensor, live feed and switched feed out to fan speed 1 and fan speed 2, so unplugging the connector and bridge from live to the other pins will run your fan on speed 1 or 2 depending on which of the pins you bridge the live to.

 

Ah...I thought that 3 wire thing was the actual power supply to the fan so i didn't understand how you guys were shorting it out. :scratch: So It's only a switch? I'll give this a try tonight and see what happens. thanks for the response

[radness 0]

 

Ah...I thought that 3 wire thing was the actual power supply to the fan so i didn't understand how you guys were shorting it out. :scratch: So It's only a switch? I'll give this a try tonight and see what happens. thanks for the response

 

I tried this, i pulled the connector (3 wire) off the rear of the fan, and connected the terminals on the fan itself to short them, nothing happened......am i doing something wrong or/and i stupid

[Supercharged 2]

Radness - it's the thermoswitch plug you need to short - it's a brass 3 pin thing half way down the right hand side of the rad (between the top and bottom hoses on a VR or G60)

 

Plug for this is on the same bit of loom as the big plug for the fan motor itself.

[radness 0]

Ah I found the switch thanks guys, ok when i short it both fan speeds work, should i permantly set it to the medium setting by keeping it shorted or should i really fix the problem? What needs replaced if the medium setting isn't coming on when it should be 90-100c water

[Jim 2]

If both speeds work, then I believe only the actual radiator fan switch (what the plug connects to in the radiator) is at fault. Not a big deal to change but it will mean draining and replacing the coolant.

 

I'm just confused with mine as the fan switch was new from VW earlier this year - rather peeved if its knackered. Really must go out and test bridging the plug pins!

[Jim 2]

Ok.... see the attached pic! Electrical stuff is not my forte so I wasn't sure which was pin 1 or 3... so using my line up as per the picture I got the following results:

 

1 + 2 = sparking from the plug, and possibly a clicking from the fan - I didn't keep it on long enough to see because of the sparks!

1 + 3 = fan comes on nice and fast / loud.

2 + 3 = nothing

 

So.... where do I go from here? I'm guessing that, regardless of me not knowing what I was doing, something isn't right there - be it the sparking, or the nothing happening bit! :(

[boost monkey 0]

1 and 2 spark cos you made a bad connection - that should be the low speed fan mode.

1 and 3 is high speed fan mode.

 

1 is the positive line, so 2 and 3 will do nothing together.

 

hth,

 

Jon.

 

p.s. do you have messenger?

[Jim 2]

1 and 2 spark cos you made a bad connection

 

Hm... i'm sure it wasn't a bad connection causing this - could try it again but was a bit afraid of all the sparking! :) Hopefully it was just a bad connection - it would point to the fan switch in the rad being to blame. Goes to show that even genuine parts can be duff sometimes :(

 

And no - no Messenger mate. Well I do, but i've not signed in for ages... might dig it out at some point :)

[boost monkey 0]

could be mate, and I could easily be wrong.

 

But i've had to jimmy plenty of mk2 fan switches in my time and i'm pretty sure that 1 + 2 = slow. I've had them spark on me too, you really have to ram the wire/ tweezers (what! they fit!) right in to make a good contact.

 

I used a paperclip once but that was too thin so to speak. It glowed red and exploded. Dying is not fun.

[boost monkey 0]

with regards to genuine parts failing. Well yeah, everything wears out. Don't take it personally buddy :D :sunny:

[Jim 2]

Ah - I was using a cable tie so even thinner than a paperclip! I best get a bit more industrial grade cabling and try again.

[Jim 2]

Well yeah, everything wears out.

 

Its only 6 months old at max - and hasn't worked right clearly since I got it....... not acceptable really!

[boost monkey 0]

ohhhhhh, that's a different story then. :sad:

[Jim 2]

I wouldn't mind so much if it wasn't a coolant out job but.. seriously, i've changed the coolant on my car so many fricking times what with duff radiators, leaking coolant hoses, leaking coolant flange, etc - I bought a VAG bit hoping it'd be a fit and forget sort of deal! Ho hum. Gonna have to go buy another especially with the air temps getting like they are..

[boost monkey 0]

Sorry to hear that Captain BURNS.

 

Maybe just put the water in it for now just to see if the new part is gonna work. Then if/when it does, you can top up with the G12.

 

C'est une bonne ide

[davidwort 0]

just changed Bally's rad fan switch at the weekend, GSF previously supplied him a 2 pin golf one so it wasn't working on 2nd speed surprisingly :lol:

we took the old 3 pin switch he had down to GSF and got them to match one in their parts bin, same pin arrangement as the connector earlier in this thread, certainly looked the part (grey body and thin metal washer attached) fitted it up and it works great, less than a tenner I think.

Now I've had sealing problems with those metal washers as they have to seal against the plastic of the back of the radiator, so always use the mk2 golf fibre washer part that you can buy separately from VW, it just has a bit more give in it to aid the seal.

[boost monkey 0]

plumber's teflon tape (that really thin white stuff that sits in screw threads) is really useful if you can't get a rad switch to seat properly :salute: